2.5 rod selection

[Powell]

K I'm trying to get a list of parts needed for a rebuild project over the upcoming winter. I'm not real familiar how changing the rods around effect the ratio and such. The question i had was that i have a 2.5L and i plan on using a g-head to replace the swirl. My next step was wondering if i could use slightly shorter rods to slightly decrease the torque to maybe even out the hp vs tq? Would that work?

Sounds like using the G-head may help but guess it takes a lil bit to tune it properly? So is it even worth thinking about?

[pobort]

when you get into changing rod lengths, you are getting into an expensive world. then you need to look at custom pistons and/or custom rods. just leave everything as it was designed use the 2.5 with the 2.5 rods and the 2.5 pistons and all will be fine and easy. unless your going for max performance shooting in the 400+hp or all out race only application looking for just a little edge over the competition, just stay with stock stuff and all will be fine

[Powell]

i was shooting for 350 and i was already planning on replacing the pistons with JE's. I wanted to replace rods anyways with lighter ones. This particular build i'd rather save the money and maybe go a lil overboard. Need something in the future i can er uh.. maybe go see some other cars.... pass each other... in boston... somewhere.... and participate....mmm yah (atleast till i ever do a 16v conversion or just buy an r/t engine) I just really want to be able to push an 8v to it's (reliable) limits

[pobort]

then start shopping for some awsome rods then have pistons made to fit the pin height you need. say crower or eagle or some other company. the 2.5 common block has a horrible rod to stroke ratio. so you want to look at a longer rod for sure which means a shorter piston pin height. however if you go to short on the pin height you need to take into account for ring positions, and clearance between the top of the rod to the bottom of the piston dish... so for all practical purposes. just get some je pistons that fit the stock 5.94" rod. 350hp is nothing to get excited about worring about exotic intermal engine parts.

[Ryan2112]

Cant you just use T2 rods? the only diffrence in the 2.5 and 2.2 are the pistons and cranks.

[pobort]

yes and no. 1986-1988 2.5's have a 6.125" long rod.

but there really is no difference between 2.2 and 2.5 turbo rods they both have full floating pins. the t2 rod might be a little stronger but not any major apreciateable amount

[Powell]

Something for me to think about then.. Thanks for the input

[mopar2ya]

any T2-T3 or T4 rod will work just fine for 375-400 h.p.

[1983Rampage]

I think that Larry (KClarry) has stock T2 rods and he is pushing 475 HP. I don't know how much more he is going to push with the car, but it is a 2.5l Hybrid turbo converted to RWD. And the 2.5l T1 and 2.2l T2 rods are the same.

[mopar2ya]

You mean 2.5 with Neon head and a Holset right? A rod wont survive to long when pushing it 3 times what the design perameters it was intended for.

[1983Rampage]

yah, I am pretty sure he is running stock T2 rods. I think he is starting to get worried on the amount the 2.5l crank and the rods can handle.

[jim34]

There was a guy with a t3 that was making 525 whp on a stock bottom end, the rods on these cars are some of the strongest factory rods ever produced, getcha some arp bolts though